贴 Haskell 代码，解一道小题。给任意字符串，找出长度最长的数字串。请随意扔砖头。 http://www.v2ex.com/t/259360#reply18

import Data.Char (isDigit)

longestInts :: String -> [Int]
longestInts xs = map (digitsToInt) $ longestLength $ extractDigits xs

extractDigits :: String -> [String]
extractDigits [] = []
extractDigits xs
| null $ dropWhile (not.isDigit) xs = []
| otherwise = (takeWhile (isDigit) $ dropWhile (not.isDigit) xs) : (extractDigits $ dropWhile (isDigit) $ dropWhile (not.isDigit) xs)

longestLength :: [[a]] -> [[a]]
longestLength xs = filter (\x -> length x == (maximum $ map (length) xs)) xs